Is this possible to create api in nintex to another external environment?
Yes, you can build your own actions . Take a look at >>> Dev Talk
I am new to Nintex.
Can please explain me in detail?
SharePoint provides API to communicate with it externally or from within using REST calls or internal web service calls, or CSOM. Nintex also provides web services to allow you to call activities to workflows using the Nintex Workflow web service. What are some of the details to what you need to accomplish from an external system?
I need to push the information through api from SharePoint Nintex environment to PHP environment.How to build an api?
Well I guess it depends on whether you need to push or pull the data. You can connect from the PHP site using CSOM and get almost any data you want on the SharePoint Site, and even start workflows. If the PHP site accepts PUT/GET JSON or web service calls then you can push data to the PHP site. Or, you can always use SQL as a middle ground very easily.
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